Gaining direct access by way of a catheter to a central vein (one which goes directly to the heart) is a common procedure that is useful for a number of medical needs, including providing fluids and nutrition, administering drugs, and allowing access to the heart for cardiovascular measurements or the implantation of devices such as pacemakers. Conventional approaches for performing central venous catheterization, as shown in FIG. 1, generally involve the placing of catheters, needles and/or wires through a percutaneous entry site 1 into a jugular vein 14 or a subclavian vein 16 and subsequent central venous cannulation. This method involves inherent risks with potentially serious consequences and adverse effects to the patient due to the technique's essentially blind puncture through the skin and percutaneous tissue (i.e., from the outside of the skin to the inside of the central vein) overlaying an accessible site of the vein. More specifically, conventional techniques, with or without fluoroscopic guidance, involve percutaneous puncture of either the jugular or subclavian vein with a hollow needle, and the passage of a guidewire into the punctured vein through the needle. Thereafter, the guidewire assists with the insertion of a vascular catheter, which then ultimately replaces the guidewire. Theses central veins are deep structures, and cannot be visualized without imaging technology. The percutaneous puncture site generally is determined by anatomic landmarks (“dead reckoning”) or, less commonly, with the aid of transcutaneous ultrasound.
While this conventional technique is usually accomplished with few or any complications and minimal pain to the patient, the technique, due to the essentially blind percutaneous puncture, inherently carries significant risks. These risks include potentially disabling or life-threatening injuries such as injury to adjacent vascular structures or nerves, occurrence of stroke secondary to vascular injury, or occurrence of pneumothorax or hemothorax secondary to lung injury. The risk of eventualities such as these are more likely when the technique is performed on children or on adult patients with challenging anatomy or conditions, such as emaciation or morbid obesity.
Safer and more cost-efficient alternative approaches to central vein access that obviate the need for blind percutaneous vein puncture would be a welcome addition to the possible approaches available to patients requiring central vein access. One such possible safer and more cost-efficient approach may include accessing the central blood vessel via a transvascular retrograde approach. The approach may be facilitated by devices and methods that provide accurate and controlled manipulation within the central blood vessel and while exiting the central blood vessel.
Reference is also made to U.S. application Ser. No. 12/366,517, entitled “Methods of Transvascular Retrograde Access Placement and Devices for Facilitating Therein”, filed Feb. 5, 2009; which is a continuation-in-part of U.S. application Ser. No. 11/424,131, entitled “Methods of Transvascular Retrograde Access Placement and Devices for Facilitating Therein”, filed Jun. 14, 2006; which is a continuation of U.S. application Ser. No. 11/381,229, filed May 2, 2006; all of which are incorporated by reference as if fully set forth herein.